Field of the Invention
The invention relates to a control device for textile machinery, more particularly a control device for a dobby.
In the modern dobbies the weaving pattern in form of electrical signals is converted into mechanical control commands The interface between the electronics and the mechanics should contain as few elements as possible elements and have a high longevity at a high switching sequence.
Known control devices (see for instance French patent FR 81 21 106) use a cam driven mechanism which drives the electromagnet armature for the selection of the YES/NO of the control command onto the yoke of the magnet, whereby the electromagnet must provide the holding force for the magnet armature which is subjected to a spring force. Aside from the cam driven mechanics for the movement of the magnet armature and the electromagnet tension and/or pressure springs such control systems also include further mechanical elements such as pawls, and levers with corresponding glide surfaces which are necessary for mechanical force amplification. If the electromagnet is to attract the magnet armature for its control function without a mechanical aid, this magnet to provide corresponding power, will become large in structural and electrical dimensions as well, due to which the switching time grows longer due to the large mass of the armature, which detrimentally influences the performance of the dobby. The named mechanical parts are a subjected to wear, are cause of noise and vibrations, and lessen the disturbance free function of the dobby over a prolonged length of operation.
The invention is based on the object of reducing the plurality of the parts necessary for the controlling of a dobby, to increase the ease of maintenance, and to attain smooth running even at high revolutions.